Bluetongue (BTV) - The Cattle Site Managing disease can be a frustrating proposition. This Guide can help you identify which disease is damaging your cattle. Bluetongue (BTV) Bluetongue is an insect-borne, viral disease primarily of sheep, occasionally goats and deer and, very rarely, cattle. The disease is non-contagious and is only transmitted by insect vectors. The disease is caused by a virus belonging to the family Reoviridae. Species affected Primarily a disease of sheep but other species such as goats, cattle, buffaloes, camels, antelopes and deer can be infected. Humans are not affected. Distribution The virus is present in most countries of Africa, the Middle East, India, China, the United States, and Mexico. Bluetongue virus infection, without associated clinical disease, is present in Southeast Asia, Papua New Guinea, northern South America and northern Australia. A strain of bluetongue virus was first identified in Australia in 1975 from trapped insects but despite its long-term presence, it has not caused any clinical disease.

Key signs The disease is characterised by fever, widespread haemorrhages of the oral and nasal tissue, excessive salivation, and nasal discharge. In acute cases the lips and tongue become swollen and this swelling may extend below the lower jaw. Lameness, due to swelling of the cuticle above the hoofs and emaciation, due to reduced feed consumption because of painful inflamed mouths, may also be symptoms of this disease. The blue tongue that gives the disease its name occurs only in small number of cases. Convalescence of surviving sheep is slow. The high fever in sheep results in wool breaks, which adds to production losses. Spread The virus cannot be transmitted between susceptible animals without the presence of the insect carriers. The incidence and geographical distribution of bluetongue depends on seasonal conditions, the presence of insect vectors, and the availability of the susceptible species of animals. The insect carriers, biting midges, prefer warm, moist conditions and are in their greatest numbers and most active after rains. Persistence of the virus Bluetongue virus does not survive outside the insect vectors or susceptible hosts. Animal carcases and products such as meat and wool are not a method of spread.

Survival of the virus within a location is dependent on whether the vector can overwinter in that area. Control strategy The strategy is to contain the outbreak and minimise trade impact by: using a combination of quarantine and movement controls to prevent spread treatments and husbandry procedures to control vectors, reduce transmission and protect susceptible animals tracing and surveillance to determine the extent of virus and vector distribution zoning to define infected and disease-free areas. There is no justification for stamping out but some animals may need to be destroyed for welfare reasons. It is not possible to eradicate the bluetongue vectors. Note: The Exotic Animal Disease Response Agreement only apply to bluetongue disease in its classical virulent form. © The State of Queensland (Department of Primary Industries and Fisheries) 1995 - 2007. Post-Mortem Blue Tongue Pictures Bluetongue is an insect-borne viral disease to which all species of ruminants are susceptible. The virus is transmitted by a small biting midge of the Culicoides genus rather than from animal to animal. The virus does not affect humans. Bluetongue is a notifiable disease and, where suspected, should be reported to Animal Health.

VLA is involved in the surveillance for the disease and was responsible for the detailed post mortem examinations of the first cases in the UK. The images below illustrate the pathology associated with this disease as shown by the first 3 cattle cases in East Anglia. Cow 1 bluetongue case – clinically affected Highland cow. Extensive superficial erosion of the muzzle with a mucopurulent nasal discharge Cow 1 bluetongue case – clinically affected Highland cow. Diffuse reddening of the dental pad with multifocal haemorrhages on the upper lip and dental pad Cow 1 bluetongue case – clinically affected Highland cow. Ocular discharge visible at the medial canthus (wrinkling of the cornea reflects post mortem change) Cow 1 bluetongue case – clinically affected Highland cow. 'Coronitis’: skin reddening around and above the coronary band intensifying distally with serous crusting at the coronary band Cow 1 bluetongue case – clinically affected Highland cow. Multifocal haemorrhages with oedema visible on the cut surface of the submandibular lymph node Cow 1 bluetongue case – clinically affected Highland cow.

Extensive ecchymotic subepicardial haemorrhages Cow 1 bluetongue case – clinically affected Highland cow. Extensive subendocardial haemorrhages in the left ventricle Cow 2 bluetongue case – Gloucester cow. Identified as PCR positive. Multiple pinpoint haemorrhages in the skin around the bases of the teats. There were also scattered petechial haemorrhages on the skin of the ventral abdomen. No other lesions distinctive of bluetongue were seen in this cow Cow 3 bluetongue case – clinically affected Friesian/Holstein cow. Focally extensive necrosis at the mucocutaneous junction of the nares. Cow 3 bluetongue case – clinically affected Friesian/Holstein cow. Focally extensive area of haemorrhage (with associated ulceration not clearly visible in this image) on the ventral surface of the tongue. There are multifocal pinpoint haemorrhages covering most of the ventral surface of the tongue Cow 3 bluetongue case – clinically affected Friesian/Holstein cow.

Focally extensive haemorrhage involving the bulbar conjunctiva with associated subconjunctival petechiation Cow 3 bluetongue case – clinically affected Friesian/Holstein cow. Generalised lymph node enlargement with oedema © 2003 Crown Copyright. Bluetongue Bluetongue Print this page Bluetongue is a notifiable disease Under Queensland legislation, if you suspect the presence of this disease in any livestock, you must report it to Biosecurity Queensland. Call us on 13 25 23. Overview Cause The disease is caused by an orbivirus virus belonging to the family Reoviridae. There are 25 serotypes of bluetongue virus (BTV) and 10 of these have been isolated in Australia. Orbiviruses are insect-borne viruses (arboviruses) transmitted by Culicoides midges. Many other non bluetongue orbiviruses are also endemic in Australia. Description Bluetongue is an insect-borne, viral disease that can affect sheep, goats, deer and cattle.

Sheep are the most seriously affected species; clinical disease and mortalities occur and production and trade losses may result. Most infections in cattle are unapparent. A number of bluetongue serotypes are present in Australia, but the severe clinical disease seen in other countries has not occurred here. Disease has been produced in experimentally infected sheep with some serotypes present in Australia. Where the disease occurs The virus is present in most countries of Africa, the Middle East, India, China, the United States, and Mexico. Bluetongue virus infection, without associated clinical disease, is present in South East Asia, Papua New Guinea, northern South America and northern Australia. In recent years the virus has been detected in northern European countries, including England, and has adapted to new Culicoides sp. vectors capable of over wintering in temperate climates. Bluetongue virus serotype 1 was first identified in Australia in 1975 from trapped insects in the Northern Territory (NT) but despite its long-term presence, it has not caused any clinical disease. Since that time nine more serotypes have been isolated in the NT.

The distribution of BTV in Australia has been monitored in the National Arbovirus Monitoring Program (NAMP) for many years and the zones of BTV virus transmission and freedom are mapped and updated regularly on the Animal Health Australia website. The virus is endemic in northern Australia (Northern Territory, Queensland and Western Australia) and its distribution extends down the east coast into New South Wales, south of Sydney, in years that are favourable for the vector. The disease in animals In countries where bluetongue disease occurs, the disease is characterised by fever, widespread haemorrhages of the oral and nasal tissue, excessive salivation, and nasal discharge. In acute cases the lips and tongue become swollen and this swelling may extend below the lower jaw. The blue tongue that gives the disease its name occurs only in small number of cases. Lameness occurs due to laminitis and inflammation of the coronary band - a dark red to purple band in the skin above the coronet is an important diagnostic sign. Emaciation and weakness develop rapidly and death occurs about six days after first signs occur. Convalescence of surviving sheep is slow. The high fever in sheep results in wool breaks, which adds to production losses.

Spread of the disease The virus cannot be transmitted between susceptible animals without the presence of the Culicoides vector. The incidence and geographical distribution of BTV depends on seasonal conditions, the presence of insect vectors, and the availability of the susceptible species of animals. The insect vectors, biting midges, prefer warm, moist conditions and are in their greatest numbers and most active after rains. Bluetongue virus does not survive outside the insect vectors or susceptible hosts. Animal carcases and products such as meat and wool are not a method of spread. Survival of the virus within a location is dependent on whether the vector can overwinter in that area. Control of the disease in animals In countries where bluetongue outbreaks occur, the strategy is to contain the outbreak and minimise trade impact by: using a combination of quarantine and movement controls to prevent spread treatments and husbandry procedures to control vectors, reduce transmission and protect susceptible animals tracing and surveillance to determine the extent of virus and vector distribution zoning to define infected and disease-free areas. There is no justification for stamping out but some animals may need to be destroyed for welfare reasons. It is not possible to eradicate the bluetongue vectors.

Vaccines are used in many countries, including Europe, to control the disease. Can people get the disease? People are not affected. Bluetongue: how to spot and report the disease - GOV.UK GOV.UK Bluetongue: how to spot and report the disease From: 30 September 2016, see all updates Applies to: England, Scotland, and Wales How to spot bluetongue, what to do if you suspect it and measures to prevent its spread. Contents other ruminants such as cows and goats camelids such as llamas Humans aren’t affected, nor are animal products or meat. The last outbreak in England, Scotland or Wales was in 2007. Bluetongue is a notifiable disease - if you suspect it you must tell the Animal and Plant and Health Agency ( APHA ) immediately. Failure to do so is an offence. Current situation There is a high risk of bluetongue type 8 spreading into the UK towards the end of summer 2016 if infected midges are carried by the wind from France to the south-east of England.

The exact level of risk depends on the level of disease in nearby areas of Europe, as well as the weather. You can get more information in the detailed assessment of the risk . How to spot bluetongue APHA will investigate if you report that you suspect a case of bluetongue. Along with the signs in this guide you can also get further details on the the clinical signs of bluetongue . In sheep In sheep the main signs of bluetongue are: ulcers in the mouth discharge of mucus and drooling from mouth and nose swelling of the mouth, head and neck and the coronary band (where the skin of the leg meets the horn of the foot) Other clinical signs include: Other animals rarely show signs of the disease. How bluetongue is spread Midges carry the bluetongue virus. The disease spreads when infected midges bite an animal affected by the disease. The midge season is normally March to September. The weather (especially temperature and wind direction) affects how the disease can spread. Preventing and controlling bluetongue You can help to prevent the disease by practising good biosecurity on your premises.

If you trade animals from outside the UK, you should consider whether they might be carrying the disease. If bluetongue is confirmed APHA will control the outbreak by following the contingency plan for exotic notifiable diseases and the bluetongue control strategy . If there is an outbreak then APHA will place movement restrictions in zones around the affected premises. Getting your animals vaccinated You can get and use authorised bluetongue vaccines for your sheep and cattle. You need to get a general licence to vaccinate your animals if they’re outside a restricted zone for bluetongue. If you’re considering whether to vaccinate your animals, you should speak to your vet about the benefits of vaccination. It can take up to 6 weeks for your animals to be fully immune as your animals must have 2 injections of the vaccine, 3 weeks apart. Movement restrictions on animals or their germplasm in a bluetongue outbreak There are currently no restricted zones for bluetongue in place for England, Scotland or Wales. If there’s a bluetongue outbreak there’ll be restrictions on where you can move live ruminants (cattle, sheep, goats, deer or camlids) and germplasm (ovum, embryos or semen).

These restrictions affect farmed and zoo animals. The controls depend on which restricted zone or area your animals or their germplasm are in and where you’re moving them to (for example for slaughter at an abattoir or to market). You may be able to move live ruminants or their germplasm out of or through a protection or surveillance zone under a specific or general licence following a veterinary risk assessment. A risk assessment is done on a case-by-case basis by APHA vets to assess the disease risk of moving animals and what needs to be done to avoid or minimise that risk. Restricted zones Restricted zones vary in size: control zone - at least 20km around infected premises protection zone - at least 100km around infected premises surveillance zone - at least 150km around the infected premises The ‘free area’ is the rest of England, Scotland and Wales that isn’t under movement restrictions. There are restrictions if you want to move your animals to and from a restricted zone for example for a show. Control zone You can’t move your ruminants between different premises within a control zone, to any other zones, or to the free area. Protection zone You can’t move animals to a premises in a control zone.

You can move ruminants within the protection zone as long as there are no clinical signs of bluetongue on the day of transport. You can move ruminants to a surveillance zone, if it passes a veterinary risk assessment, if they’re either: for slaughter under licence at a designated abattoir - the Food Standards Agency will identify slaughterhouses to receive animals from a restricted area during any outbreak the animals meet meet the EU exemption criteria of annex 3 sections 5 to 7 (for example negative test or vaccinated) You can only move ruminants and their germplasm to a non-EU country (a ‘third country’) if they meet the import requirements of the destination country. Contact the APHA Centre for International Trade, Carlisle for more information (for example on a country’s requirements). You can only move animals and their germplasm to a third country if they meet the import requirements of the destination country. Surveillance zone You can’t move animals to a control zone. There are no restrictions on moving animals to a protection zone. You can move ruminants within the surveillance zone as long as there’s no clinical signs of bluetongue on the day of transport.

You can move ruminants and germplasm to a free area, Northern Ireland, or other EU countries if they pass a veterinary risk assessment or have a health certificate and: You can only move ruminants and their germplasm to a third country if they meet the import requirements of the destination country. Contact the APHA Centre for International Trade, Carlisle for more information (for example on a country’s requirements). Moving live ruminants from a disease free area through a Restricted Zone You need to be licensed if you plan to transport animals from a disease free area to another disease-free area through a restricted zone. This is likely, following a veterinary risk assessment, to be by meeting the requirements of a general licence that would be published here in the event of an outbreak. Bluetongue legislation The main EU legislation on bluetongue is Directive 2007/75 . The main domestic legislation is the Bluetongue Regulations 2008 . Amendments to allow vaccination under licence were made by the Bluetongue (Amendment) Regulations 2012 .

Fact Sheet - Bluetongue - Animals - Canadian Food Inspection Agency Canadian Food Inspection Agency Fact Sheet - Bluetongue What is Bluetongue? Bluetongue is a disease of domestic and wild ruminants that is spread by insects, particularly biting midges of the Culicoides species. The range of domestic animals that can be infected with bluetongue virus includes: domestic cattle Bluetongue can also affect wild animals such as: bighorn sheep white-tailed deer and most other even-toed hoofed animals Where is bluetongue found? Bluetongue can be found anywhere the midges that transmit the virus are present. It is commonly found in the U.S. , Mexico, Australia, Africa, the Middle East, the Indian subcontinent and China. Bluetongue is also spreading northwards in Europe. Most of Canada is currently free of the disease. Over the past 30 years, there have been occurrences of bluetongue in the Okanagan Valley, British Columbia, which are believed to be the result of wind-borne introduction of infected midges from the U.S. In September 2015, bluetongue was confirmed in southwestern Ontario.

How is bluetongue transmitted and spread? Bluetongue is transmitted from animal-to-animal by a specific species of biting Culicoides midge. In Canada, the presence of the virus is usually restricted to late summer and early fall, since conditions must be warm enough for the bluetongue virus to multiply within the midge (13° C to 35° C ). Midge activity ceases with the first hard frost. There is no evidence that bluetongue is able to survive winter in Canada. The virus does not survive in the environment outside a midge or its animal host. It cannot be spread through contact with animal carcasses and products such as meat and wool. Is bluetongue a risk to human health? No. There is no risk to human health associated with bluetongue. What are the clinical signs of bluetongue? Signs of clinical disease vary among different species. Infection is inapparent in the vast majority of species. Cattle, goats and elk, for example, are affected by a very mild, self-limiting infection. Bluetongue can cause serious illness and death in sheep as well as deer and potentially other wildlife.

There is no cure and death may occur within seven days. In sheep, the symptoms of bluetongue include: fever reddening of the lining of the mouth and nose swelling of the lips, tongue and gums difficulty swallowing and breathing a swollen, purple-coloured tongue (hence, the name bluetongue) lameness How is bluetongue diagnosed? Tentative diagnosis of bluetongue in sheep can be made based on the appearance of clinical signs and lesions. The presence of midge vectors is also taken into account. Laboratory tests are required to confirm the presence of the bluetongue virus. How is bluetongue treated? There is no effective treatment for bluetongue. Vaccines are available for certain types of the disease and are used in Africa and Asia. What happens when bluetongue is found? The types of bluetongue considered endemic in the U.S. (serotypes 2, 10, 11, 13 and 17) are immediately notifiable under the Health of Animals Regulations . Laboratories are required to report confirmed diagnoses to the CFIA . This enables prevalence verification and supports international reporting and certification requirements.

All remaining types of bluetongue, exotic to the U.S. , are federally reportable under the Health of Animals Act . This means that all suspected or confirmed cases must be reported to the CFIA . ENY-743/IN768: Bluetongue Walter J. Tabachnick, Chelsea T. Smartt, and C. Roxanne Connelly 2 What is bluetongue? Bluetongue is a disease of ruminant livestock that is caused by the bluetongue virus. Bluetongue virus does not cause disease in humans. This virus is transmitted to livestock by selected species in the genus Culicoides (Diptera: Ceratopogonidae). These small insects are biting midges and in some areas are called no-see-ums, sand flies or punkies. Bluetongue virus was among the first recognized insect borne viruses. The disease was first described in livestock in South Africa in 1902. Bluetongue virus is widely distributed throughout the tropical, subtropical and temperate regions of the world wherever different competent species of Culicoides occur.

Bluetongue outbreaks can result in millions of dollars in losses due to the impact on livestock health and notably in the loss of markets for livestock due to regulatory restrictions on animal movement to limit the spread of the disease. The virus Bluetongue virus, or BTV, is a member of the Orbivirus genus in the family Reoviridae. BTV is related to other orbiviruses that also cause disease in animals like African horse sickness and epizootic hemorrhagic disease viruses. The orbiviruses contain genomes that are in the form of RNA segments. BTV occurs in the form of 24 different serotypes (a serological form of the virus) and these serotypes are distributed in different regions of the world. It is thought that the distribution of the different serotypes in different regions is influenced by the different species of Culicoides that are present in specific regions. For example, historically only five BTV serotypes, BTV-2, 10, 11, 13 and 17 have occurred in the U. S.

Surveillance in the Caribbean Basin showed the presence of BTV-1, 3, 4, 6, 8, 8, 12, 14, and 17. It is believed that the difference in the types of serotypes in these two regions is due to different Culicoides vectors in the two regions. In the U. S. Culicoides sonorensis is the primary vector, while in the Basin region the vector is Culicoides insignis. In other regions of the world, i.e., Africa, South America, Asia, and Europe, there are additional BTV serotypes and each region has different species of Culicoides that are the primary vectors. What are the clinical signs of bluetongue in livestock? Bluetongue virus may infect several different domestic and wild ruminant species including cattle, deer, goats, and sheep.

However clinical signs are most apparent in sheep where signs include 5-7 days of increasing temperature (up to 107.6oF), excessive salivation, hyperemia and swelling of the nasal and buccal mucosa, hemorrhaging in the mucosal membranes in the mouth, oral erosions, swollen tongue, loss of wool, depression and hemorrhages in the coronary bands of the hoof that often result in lameness, and difficulty standing (Fig. 1) Figure 1. Sheep exhibiting hunched appearance due to pain in inflamed coronary bands. Credit: A. J. Leudke, USDA/ARS [Click thumbnail to enlarge.] Sheep with lesions in the mouth and esophagus may vomit and this may lead to aspiration of the ruminal contents, pneumonia and death. Bluetongue can be a severe disease in sheep with mortality varying from 5-80% depending on the virus serotype and on the immune status of the sheep populations. Although cattle can serve as reservoirs for BTV, clinical disease in cattle has generally been rare. When this has been encountered, clinical disease is usually evident in fewer than 5% of infected animals, and there is very rarely any mortality.

Cattle develop a prolonged viremia lasting several weeks. This is believed to enable the virus to survive during cold winters in the absence of insects, or at other times when vector populations are absent or reduced. Therefore, cattle are considered reservoirs for BTV and a means of introducing BTV into different areas through cattle movement and trade. Early prenatal infection with BTV may lead to embryonic death in cattle so that epidemics can influence cattle reproduction. However cattle fetuses infected later in gestation usually survive without persistent infection and these animals develop antibodies to the specific infecting virus serotype. Impact Bluetongue can have a severe impact on the livestock economy of a country or region. The disease itself can cause catastrophic losses to sheep populations. Although mortality to bluetongue is often low, it is not uncommon to see mortality rates approaching 50% - 100% in susceptible flocks, and there are other losses due to morbidity and the need to provide care for sick animals. Costs associated with morbidity of sick animals include weight loss, reduced milk yield, abortion and associated veterinary costs.

During a BTV-2 epidemic in Italy in 2000-2001, approximately 263,000 diseased sheep and goats were reported (18% morbidity) and 48,000 sheep and goats died (3% mortality). During a second epidemic in 2001-2002, approximately 251,000 diseased sheep and goats were reported (18% morbidity) and 73,000 sheep and goats died (5% mortality) (Calistri 2004). In 2007 BTV-8 outbreaks occurred on over 20,000 farms in Germany with disease in ca, 35,000 cattle, sheep or goats. The indirect costs associated with bluetongue can be much greater than the direct costs. Bluetongue is a "List A" disease of the Office of International Epizootics (OIE). List A diseases are those diseases which can spread rapidly and that have a considerable impact on the health of livestock.

List A diseases are notifiable to the OIE, and often used as non-tariff trade barriers to prevent livestock from moving and potentially spreading disease. Livestock from bluetongue endemic areas, or regions where there are outbreaks, can be prevented through regulatory policy from moving to regions considered bluetongue-free. The economic impact in reducing livestock movement and trade can be considerable. Additional costs for bluetongue come from the required testing for the virus in animals being considered for movement. The impact on cattle industries is through the effects of trade barriers. Bluetongue positive cattle are not allowed to be moved from outbreak areas because of the prolonged viremias. Cattle are capable of infecting Culicoides and spreading the virus for as along as a month after infection. In 2007, a BTV-8 outbreak in France was estimated to cost $1.4 billion. Losses were largely due to the inability to trade cattle, a very substantial industry in France, on the international market. In 2007 a BTV-8 outbreak in the Netherlands cost approximately $85 million. The southern regions of the U. S.

have been endemic for certain BTV serotypes for many years though animal disease has been rare. Nevertheless the impact on the U. S. has been losses due to restrictions on the international cattle trade in livestock and germ plasm to regions considered bluetongue-free like some countries in the European Union. The U. S. losses in trade and associated testing of cattle for BTV status has been estimated at $130 million annually. How is bluetongue transmitted to livestock? The cycle of transmission is from a competent Culicoides to a ruminant animal, back to a susceptible Culicoides, to a ruminant and back to a Culicoides, etc. The female Culicoides requires a blood meal in order to lay eggs. Different Culicoides species prefer different types of habitats to lay eggs. Culicoides sonorensis prefers heavily organic rich water, with high manure content for egg laying and subsequent larval development. Some African Culicoides vectors lay eggs directly in the deposited dung of ruminants. Both types of insects, therefore, lay their eggs and complete larval development near ruminant livestock habitat. Figure 2.

A Culicoides sonorensis female after blood feeding Credit: E. T. Schmidtmann, USDA/ARS [Click thumbnail to enlarge.] How is bluetongue diagnosed? In regions with known transmission, Bluetongue can be diagnosed based on the characteristic lesions in susceptible animals. However, the diagnosis should always be confirmed by virus isolation and identification using any of a variety of available methods capable of detecting BTV in blood. A rise in BTV antibody may also be used to confirm a diagnosis. There are many immunological tests that can be used including enzyme immunoabsorbant assay, cell culture or inoculation of the blood into embryonated chicken eggs. Faster identification of the BTV in blood or other infected tissue can be achieved using polymerase chain reaction methods capable of detecting virus RNA. What is the cure? As with the other arthropod-borne viruses, there is no "cure" or effective treatment for bluetongue disease other then treating the clinical signs in an attempt to reduce the severity. Where does bluetongue occur? BTV occurs wherever there are species of Culicoides capable of transmitting it to animals.

Historically BTV serotypes occur in Africa, Asia, South America, North America, Middle East, India, Australia (Fig. 3). Figure 3. Distribution of BTV serotypes and major vectors. Credit: W. J. Tabachnick, UF/IFAS [Click thumbnail to enlarge.] U.S. BTV serotypes 1,10,11,13 and 17 have been found in the southern and western states where they are transmitted by Culicoides sonorensis (Fig 2). The northern states do not support Culicoides sonorensis populations, and this region of the U.S. and adjacent regions of Canada are considered BTV-free. Europe and the Mediterranean Basin had been BTV free until the beginning of 2001 when BTV serotypes began to appear in Italy causing outbreaks and considerable economic losses in sheep populations. Substantial outbreaks of BTV-8 occurred in northern Europe livestock during 2006 and 2007 transmitted by European Culicoides for the first time. In 2007 BTV in the form of BTV-8 entered the United Kingdom causing outbreaks on farms in Southern England.

The reason for the expansion of the range of BTV into Europe is unknown. The recent spread of different BTV serotypes to northern Europe is alarming. The spread has been facilitated by a few species of northern European Culicoides. It is also alarming that these outbreaks have been accompanied by the appearance of more clinical cases of bluetongue in cattle than had ever been seen elsewhere. What about Florida? Culicoides sonorensis occurs throughout Florida. The South American vector of BTV, Culicoides insignis, occurs in the southern half of Florida. As a result Florida livestock are exposed to BTV. Tests on about 240 Florida cattle showed that approximately 40% of Florida cattle had antibody to BTV signifying that they had been previously infected with either BTV-10, 11, 13, or 17 (Metcalf et al. 1981). Fortunately clinical disease has not occurred, but Florida cattle are restricted in international trade to BTV-free countries. In 2001 tests on a few sick sheep, goats and two cattle resulted in the first identifications of new BTV serotypes in the U. S.

Between 2001 and 2007, 18 identifications were made and included the following exotic BTV serotypes: BTV 3,5,6,14,19,22. It is noteworthy that two cattle were found with clinical signs. How these serotypes entered Florida, where they came from, how far they have spread, what their effect will be on livestock health and well being in Florida and the rest of the U. S. is unknown. How can it be prevented? The most effective preventive measure to protect livestock from BTV is through vaccination. There are a variety of different BTV vaccines available but to be effective the vaccine must be specifically for the serotype that is being transmitted and causing the cases in the field. Vaccines exist in a variety of forms. Modified live or attenuated vaccines are available for several different serotypes and have been widely used in South Africa. Unfortunately, though effective and cheap to produce these vaccines produce viremia in vaccinated animals that can infect Culicoides, and there is evidence that the modified virus can revert to virulence. In addition attenuated vaccines can cause reproductive problems if given to sheep during reproduction.

Killed vaccines consist of completely inactivated virus and are available. Culicoides control through adult suppression, larval control through reduction of larval habitat, housing animals indoors when Culicoides activity is highest or using repellents to protect animals from attack have not been effective in mitigating outbreaks of bluetongue. References Calistri, P., Giovannini, A., Conte, A., Nannini, D., Santucci, U., Patta, C., Rolesu, S., and Caporale, V. 2004. Bluetongue in Italy. Vet. Ital. 40: 243-251. MacLachlan, N.J. and Pearson, J.E. (Eds.). 2004. Bluetongue. Proceedings of the Third International Symposium. Vet. Ital. 40 (3): 1-730. Metcalf, H.E., Pearson, J.E. and Klingsporn, A.L. 1981. Bluetongue in cattle: A serological survey of slaughter cattle in the United States. Amer. J. Vet. Med Res.

42: 1057-1061. Tabachnick, W.J. 1996. Culicoides variipennis and bluetongue-virus epidemiology in the United States. Ann. Rev. Entomol. 41: 23-43. Walton, T.E. and Osburn, B.I. (Eds.).1992. Bluetongue, African Horse Sickness and Related Orbiviruses. Proceedings of the Second International Symposium. CRC Press, Boca Raton. 1042 pp. Footnotes 1. This document is ENY-743 (IN768) on mosquito tranmsmitted disease, is one of a series of the Entomology and Nematology Department, UF/IFAS Extension, Gainesville, FL. Publication date: April 2008. Reviewed February 2014. For more publications related to horticulture/agriculture, please visit the EDIS website at 2. Walter J. Tabachnick, professor and director, Chelsea T. Smartt, assistant professor, and C.

Roxanne Connelly, associate professor, Department of Entomology and Nematology, Florida Medical Entomology Laboratory, UF/IFAS Extension, Vero Beach, FL. The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office. U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.

NJDEP - News Release 14/P112 - Division of Fish and Wildlife Confirms Bluetongue Virus in Two Deer; Department of Agriculture Urges Livestock Owners to Report Any Suspected Animal Illnesses Contact: Lawrence Hajna (609) 984-1795 Bob Considine (609) 984-1795 Lynne Richmond, Agriculture (609) 633-2954 DIVISION OF FISH AND WILDLIFE CONFIRMS BLUETONGUE VIRUS IN TWO DEER; DEPARTMENT OF AGRICULTURE URGES LIVESTOCK OWNERS TO REPORT ANY SUSPECTED ANIMAL ILLNESSES (14/P112) TRENTON – The Department of Environmental Protection’s Division of Fish and Wildlife has confirmed New Jersey’s first cases of bluetongue virus in two deer. The virus was confirmed in one deer that died in Basking Ridge, Somerset County on Sept. 4 and another that died in Stirling, Morris County on Sept. 19.

The clinical signs of bluetongue are identical to epizootic hemorrhagic disease (EHD), which has occurred seven times in the state since 1995. “The bluetongue virus is widely distributed in the United States, but has not been previously found in deer in New Jersey,” said Division of Fish and Wildlife Director Dave Chanda. “Both diseases are spread to animals by the bite of a certain type of midge. Neither disease can be transmitted to people. While EHD is only found in deer populations, the bites of the midge can transmit bluetongue to certain types of livestock.” The clinical signs of disease caused by both viruses are identical, and the two can only be differentiated by testing and virus isolation. The potential for disease transmission will end when frost kills the midges. People are not at risk by handling infected deer, being bitten by infected midges, or eating infected deer meat, although the Division of Fish and Wildlife strongly advises against consuming meat from any game animal that appears ill. Unlike EHD, bluetongue is a disease of concern in ruminant livestock such as sheep, llama, alpaca, goats, and cows.

It causes a similar disease in all ruminants with variable mortality rates depending on virus strain and livestock species affected. Horses are not affected. Effects are usually most severe in improved sheep breeds such as fine wool and mutton breeds. No cases of livestock illnesses have been reported. Livestock that appear to exhibit any of the symptoms associated with bluetongue should be reported to the New Jersey Department of Agriculture, Division of Animal Health at (609) 671-6400. The New Jersey Department of Agriculture’s Animal Health Diagnostic Laboratory (AHDL) can assist in diagnosing suspected bluetongue cases by offering testing and necropsy services.

The AHDL can be contacted by calling (609) 406-6999 or e-mailing jerseyvetlab@ag.state.nj.us More information about the tests offered can be found on the AHDL website: Deer that appear to exhibit any of the symptoms associated with bluetongue or EHD should be reported to the Division of Fish and Wildlife Bureau of Wildlife Services at (908) 735-7040 or the Division’s Office of Fish and Wildlife Health and Forensics at (908) 236-2118. Both diseases are contracted from the bite of a species of midge fly known as Culicoides sp. Outbreaks typically begin in late summer. Symptoms in deer may include difficulty standing, drooling, and emitting foam from the mouth or nose. Because the disease causes fever, sick or dead deer are often seen in or near water. Clinical signs in livestock include, but are not limited to, fever, listlessness, edema and congestion of mouth, nose, eyes, and coronary bands, mouth sores, lameness and a characteristic swelling of the tongue. Affected animals may act as carriers for an extended period after recovery.

### Bluetongue Bluetongue Bluetongue Blue Tongue is a notifiable disease Bluetongue is a non-contagious, viral disease affecting domestic and wild ruminants (primarily sheep and including cattle and goats), that is transmitted by insects, particularly biting midges. The severity of disease varies among different species with symptoms being most severe in sheep resulting in death, weight loss and disruption in wool growth. In highly susceptible sheep, morbidity can be as high as 100%. Mortality averages from 2-30% but can be as high as 70%. Cattle often have a higher infection rate than sheep and demonstration and severity of clinical signs varies depending on the strain of virus. Where is the disease found? Blue Tongue has a significant global distribution in regions where the insect vector (ie, biting midges species Culicoides) is present, including Africa, Asia, Australia, Europe and North America. The virus is maintained in areas where the climate will allow biting midges to survive over winter. The geographical distribution of the insect vector species generally limits the distribution of the disease. Generally, sheep found in areas where the disease is endemic are naturally resistant to Blue Tongue.

Outbreaks occur when susceptible sheep, particularly European breeds are introduced to endemic areas, or when the virus is introduced to a region by windborne movement of infected Culicoides. Occurrence of Blue Tongue generally parallels vector activity surging during periods of high temperature and rainfall and subsiding with the first frost or severe cold weather. How is the disease transmitted and spread? The insect vector is the key to transmission of Blue Tongue virus between animals. Vectors are infected with Blue Tongue virus after ingesting blood from infected animals. Without the vector, the disease cannot spread from animal to animal. Blue Tongue virus transmission can occur throughout the year, particularly during rainy periods. Infected cattle play a significant role in maintaining the virus in a region. Cattle may serve as a source of virus for several weeks while displaying little or no clinical signs of disease and are often the preferred host for insect vectors. The virus has been found in semen from infected bulls and rams and can be transmitted to susceptible cows and ewes but this is not a significant mechanism of transmission. Virus can also be transferred through the placenta to the fetus. The Blue Tongue virus is not transmitted through contact with animals, wool or consumption of milk.

There is no public health risk associated with Blue Tongue. What are the clinical signs of the disease? The appearance of clinical signs in cattle will depend on the strain of virus and it is possible that cattle will show no signs of illness; however, clinical signs have included: nasal discharge swelling of the head and neck conjunctivitis (red and runny eyes) swelling inside and ulceration of mouth swollen teats

Question: Which animals are mainly affected by the disease "blue tongue"?
Answer: SHEEP